The OP animates several scenes from the original manga, using a lot of cell shading to give it an animated, quasi 3D look and feel.
However, it gives the characters a feel that’s kind of “Uncanny Valley”-ish.

Episode 2: “A Letter From the Past”

Artwork seemed a tad too angular, especially when compared to the previous episode and the next. I guess that is to be expected, since this is the first episode with the regular character designs.